By default, some HTML tags are removed by the SafeHTML parser to protect against potentially dangerous code. The list of tags that are removed can be found on the SafeHTML page.

It is possible to allow all HTML tags to be used, but this is a big security risk. Use with caution.
To allow all HTML tags, edit the wikka.config.php file and change the double_doublequote_html value to "raw".
Possible values of double_doublequote_html: